path: root/net/mac80211/status.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
 * Copyright 2008-2010	Johannes Berg <johannes@sipsolutions.net>
 * Copyright 2013-2014  Intel Mobile Communications GmbH
 */

#include <linux/export.h>
#include <linux/etherdevice.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>
#include "ieee80211_i.h"
#include "rate.h"
#include "mesh.h"
#include "led.h"
#include "wme.h"


void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
				 struct sk_buff *skb)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	int tmp;

	skb->pkt_type = IEEE80211_TX_STATUS_MSG;
	skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
		       &local->skb_queue : &local->skb_queue_unreliable, skb);
	tmp = skb_queue_len(&local->skb_queue) +
		skb_queue_len(&local->skb_queue_unreliable);
	while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
		ieee80211_free_txskb(hw, skb);
		tmp--;
		I802_DEBUG_INC(local->tx_status_drop);
	}
	tasklet_schedule(&local->tasklet);
}
EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);

static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
					    struct sta_info *sta,
					    struct sk_buff *skb)
{
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	struct ieee80211_hdr *hdr = (void *)skb->data;
	int ac;

	if (info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
			   IEEE80211_TX_CTL_AMPDU |
			   IEEE80211_TX_CTL_HW_80211_ENCAP)) {
		ieee80211_free_txskb(&local->hw, skb);
		return;
	}

	/*
	 * This skb 'survived' a round-trip through the driver, and
	 * hopefully the driver didn't mangle it too badly. However,
	 * we can definitely not rely on the control information
	 * being correct. Clear it so we don't get junk there, and
	 * indicate that it needs new processing, but must not be
	 * modified/encrypted again.
	 */
	memset(&info->control, 0, sizeof(info->control));

	info->control.jiffies = jiffies;
	info->control.vif = &sta->sdata->vif;
	info->control.flags |= IEEE80211_TX_INTCFL_NEED_TXPROCESSING;
	info->flags |= IEEE80211_TX_INTFL_RETRANSMISSION;
	info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;

	sta->status_stats.filtered++;

	/*
	 * Clear more-data bit on filtered frames, it might be set
	 * but later frames might time out so it might have to be
	 * clear again ... It's all rather unlikely (this frame
	 * should time out first, right?) but let's not confuse
	 * peers unnecessarily.
	 */
	if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
		hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);

	if (ieee80211_is_data_qos(hdr->frame_control)) {
		u8 *p = ieee80211_get_qos_ctl(hdr);
		int tid = *p & IEEE80211_QOS_CTL_TID_MASK;

		/*
		 * Clear EOSP if set, this could happen e.g.
		 * if an absence period (us being a P2P GO)
		 * shortens the SP.
		 */
		if (*p & IEEE80211_QOS_CTL_EOSP)
			*p &= ~IEEE80211_QOS_CTL_EOSP;
		ac = ieee80211_ac_from_tid(tid);
	} else {
		ac = IEEE80211_AC_BE;
	}

	/*
	 * Clear the TX filter mask for this STA when sending the next
	 * packet. If the STA went to power save mode, this will happen
	 * when it wakes up for the next time.
	 */
	set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
	ieee80211_clear_fast_xmit(sta);

	/*
	 * This code races in the following way:
	 *
	 *  (1) STA sends frame indicating it will go to sleep and does so
	 *  (2) hardware/firmware adds STA to filter list, passes frame up
	 *  (3) hardware/firmware processes TX fifo and suppresses a frame
	 *  (4) we get TX status before having processed the frame and
	 *	knowing that the STA has gone to sleep.
	 *
	 * This is actually quite unlikely even when both those events are
	 * processed from interrupts coming in quickly after one another or